Bicycle handlebars and their supporting structure are exposed to relatively severe impact loads. This is particularly true for competition mountain bicycles. In a rough off-road environment, handlebar impact loads in excess of 500 lbf can occur. This level of loading imposes severe structural demands on the handlebar clamping mechanism. Also, in competition riding, the ease (hence, speed) with which the handlebar assembly can be adjusted (or replaced) is important.
Current handlebar clamping methods are not very efficient. They tend to be relatively heavy and bulky and are not easily adjusted without the use of special tools. To the serious competition bicyclist, these are important factors in the design. Prior art systems are also relatively expensive to produce. Some require labor intensive welding operations. Other require a number of precision machining steps. Many of the prior art are produced from (or partially from) solid bar stock. This results in a considerable amount of material waste and an excessive amount of machine and labor time for the tooling operations.
The primary objectives of this invention are to provide a handlebar to steerer clamping device which: 1) improve the fatigue characteristics of the handle-bar to steerer connection, 2) reduces material weight and cost, 3) reduces manufacturing costs and 4) improves the adjustability of the handle-bar assembly.